Such a hair-care appliance is known from U.S. Pat. No. 4,877,042. A hair-care appliance is to be understood to mean an electrically heated device, which may or may not incorporate a blower, for curling, shaping or styling the hair. Such appliances include a hair brush, a hair curler and hair comb without blower, and a hair dryer and hot air brush with blower. Grooming the hair is often effected by first moistening the hair and then shaping it into the desired style with the styling means of the hair-care appliance, in combination or not in combination with a comb or curlers. The hair is dried by the heat of the heating element, for which care must be taken that the hair cannot become too dry because dry hair is more liable to be damaged. For this purpose, the known hair-care appliance comprises electrodes which contact the hair and a measurement circuit which measures the resistance of the hair. The resistance of the hair depends on the moistness of the hair. Dry hair has a comparatively high resistance and wet hair has a comparatively low resistance. The resistance variation is fairly large and therefore it is quite difficult to determine when the resistance passes a certain threshold, so as to allow signalling that the moistness of the hair has reached the desired value.